DIAGNOSTIC TESTS*
Measure Fuel Pressure
• The engine will not perform correctly with
low fuel pressure. Fuel pressure can be
measured at the secondary filter housing
by removing the fuel pressure test port
plug and install the ICP System Test
Adapter (ZTSE4594). Connect the Fuel
Pressure Gauge (ZTSE4681) to the ICP
System Test Adapter. Turn the key switch
to the ON position and measure the fuel
pressure. The following pressure
minimums should be met:
Cranking
20 psi
Idle
50 psi
High Idle/No load
50 psi
Full load @ rated speed 50 psi
• If fuel pressure does not meet the
minimum, verify there is fuel in the tank and
the pump is running. Then check for fuel
aeration, primary and secondary filter
condition, pump inlet restriction, pump
deadhead pressure, and pressure
regulator operation.
Check for Fuel Aeration
• The engine will not operate correctly with
aerated fuel. Aeration can be checked
visually using a clear hose and valve.
• Remove the fuel pressure test port plug.
Connect the Fuel Pressure Gauge
(ZTSE4681) to the secondary fuel filter
housing using the ICP System Test
Adapter (ZTSE4594). With the key switch
ON, open the valve to allow fuel to flow
into a clean container. Observe the fuel
flow. Opening the system to install the
hose will allow some air to enter the
system. This air will be visible in the fuel
flow initially but should clear within a few
seconds.
• If the fuel continues to show signs of
aeration, check the suction side of the
system for air leaks.
94
International
®
VT 275 V6 Engine
*Consult service literature for latest information before attempting any repairs
IIC
CP
P S
SYYS
STTEEM
M TTEES
STT AAD
DAAP
PTTEER
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FFU
UEELL P
PR
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SS
SU
UR
REE G
GAAU
UG
GEE
FFU
UEELL P
PR
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SS
SU
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REE G
GAAU
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GEE